Welcome to the forum.
We are from Sartell, MN.
If you like to camp at state parks try Father Hennepin in Isle, St. Croix outside of Hinckley, or Itasca State park.
If you like more amenities try:
Woodsong Resort outside of Ogilvie,
Pete's Retreat in Malmo,
Keisler's RV Resort in Waseca,
Crow Wing Lake Campground outside of Brainerd
Burlington Bay Campground in Two Harbors,
Grand Marais Recreation Center in Grand Marais,
Indian Point Campground in Duluth across from the Duluth Zoo,
Spirit Mountain Campground on top of the hill by the rest area.
You may also try these web sites.
Minnesota Campground Reviews - The Best of Minnesota Camping - RV Park Reviews or this one
State park map: Minnesota DNR
If you like to camp on the cheap try Cross Lake Campground in Cross Lake, Very nice park in the middle of lake country.
There are many more in the state that we have tried and I would be happy to supply more if you need. Just PM me.